On May 27 the U.S. Government released a report, The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in The United States, with strong conclusions that ought to suffice to establish an “endangerment” finding under which EPA would regulate carbon dioxide emissions.

Note of clarification: The report titled The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in the United States, released on May 27 and identified as Climate Change Science Program Synthesis and Assessment Product 4.3 Final Report, and the report titled Scientific Assessment of the Effects of Global Change on the United States, released on May 29 by the White House Office of Science and Technology Policy, are two different documents. There is overlap in the issues they address.

In April 2007 the U.S. Supreme Court ruled in the case of Massachusetts et al. v. Environmental Protection Agency that EPA has the legal authority to regulate carbon dioxide emissions from motor vehicles as a pollutant under the Clean Air Act, and must regulate under that law if the agency determines that CO2 emissions lead to an endangerment of public health or welfare. In December 2007, EPA informed the White House of its finding that carbon dioxide emissions are a danger to public welfare in the United States and, pursuant to that endangerment finding, proposed to regulate CO2 emissions from motor vehicles. Since then, however, the agency has taken no further action. In a March 12 letter to EPA Administrator Stephen Johnson, House Oversight and Government Reform Committee Chairman Henry Waxman cited information provided to the Committee by seven senior EPA officials on how a major effort to comply with the Supreme Court ruling in Massachusetts v. EPA has beeen blocked.

The EPA “endangerment” document has not been released publicly. However, a reading of the new Climate Change Science Program synthesis report, The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in The United States, released on May 27, provides all the evidence that should be required (if any additional evidence can be said to be needed) in order to trigger significant steps to regulate greenhouse gas emissions -– both through the Clean Air Act and via the implementation of emissions cap and trade legislation.

See the excellent page 2 story on the report in the Washington Post May 28 by Juliet Eilperin, “Report Details Effects of Climate Change Across U.S.”

Also see Andrew Revkin’s article, “New Climate Report Foresees Big Changes,” in the New York Times May 28.

An online article by Bradford Plumer in The New Republic May 28, “No Need to ‘Wait and See’,” adds this perspective:

Looks like we won’t have to wait 50 years to see the effects of rising global temperatures, after all. According to a new study [LINK] by the U.S. Climate Change Science Program, those changes are already well underway across the country:

“Climate change is currently impacting the nation’s ecosystems and services in significant ways, and those alterations are very likely to accelerate in the future, in some cases dramatically,” the report says. “Even under the most optimistic CO2 emission scenarios, important changes in sea level, regional and super-regional temperatures and precipitation patterns will have profound effects.” …

It’s a good reminder, too, that even if the world does get its act together to avert runaway global warming (which could very well happen if temperatures rise more than 2 degrees above pre-industrial levels, thanks to a whole gamut of carbon-cycle feedbacks), there are still plenty of changes that won’t be preventable, and the United States ought to start worrying about adaptation as well as mitigation. John McCain’s big climate speech was sharp on this point, although massive adaptation efforts are certainly hard to square with his “slap a price on carbon and then get out of the way” philosophy.
Also, one other footnote here: Back in 2005, the CCSP turned into something of a hornet’s nest when one of its senior associates, Rick Piltz, came forward and accused a White House official of editing government climate reports in order to emphasize doubts about global warming and downplay the downsides. (The appointee in question, Philip Cooney, ended up resigning and scurried back to the oil industry.) Anyway, it’s probably never safe to assume that the White House is being totally hands-off on this stuff, but the latest report does sound a lot more severe than anything else the administration has released to date, so maybe the appointees are finally backing off, at least on this front.